In the packaging of certain products, such as freshly roasted coffee beans, in a sealed flexible container or pouch a significant amount of gas is released from the product which creates considerable pressure within the pouch and which is capable of rupturing the pouch. Consumers are reluctant to purchase or use a product within a bloated container, so it is important to avoid gas build up within a flexible container. Thus, it is important to provide a flexible container which provides for the release of gases from products packaged in a sealed flexible container or pouch. Moreover, many products packaged in flexible containers are damaged by oxygen entering the flexible container and the means which allows gas to escape from a sealed flexible pouch must also prevent air from entering the sealed container.
Many flexible container or pouch structures have been devised having a self-sealing gas valve which allows gas within a sealed flexible pouch to escape before the internal gas pressure causes the pouch to have a bloated appearance which causes the pouch to rupture. One such recent U.S. patent typical of the prior art sealed flexible pouch structures having a pressure sensitive gas valve is U.S. Pat. No. 5,059,036 issued to Richison et al. The Richison et al structure and all other know relevant prior art structures have self-sealing pressure sensitive gas relief valves which are mounted on a wall of the container as an adjunct to the container, usually after the container has been formed, in a time consuming operation which increases the cost of the pouch significantly due to increased labor and material costs.